True enough! But then, he didn't say it was CSV. He said it was "tab delimited".

CSV is a rather more robust format that permits fields in which you can escape your separator, have embedded newlines, etc. "Tab delimited" generally means a file where records are delimited by newlines, fields are delimited by tabs, and fields may not contain newlines or tabs. It's common. And splitting on tabs works very nicely for it without requiring additional dependencies and overhead.